As soon as you launch the application, SYQEL Desktop will attempt to connect to your Mac’s microphone.
Click Allow Access so that the app can connect to your mic input and enable you to preview the audio responsiveness of the visuals.
Beyond your default Mic input, on a Mac – the app may show you the option to connect to your iPhone’s mic (if you own an iPhone) or a virtual audio input, if you already have one set up.
You can switch between audio inputs at anytime, without having to stop the visualizer.